Molecular Epidemiology of Vancomycin-Resistant Enterococcus Faecalis Among Patients of Transplantology Wards

Objective. Vancomycin-resistant enterococci (VRE) require epidemiological monitoring especially in transplantation wards. The aim of our work was to perform a molecular analysis of vancomycin-resistant Enterococcus faecalis (VREfl) strains among solid organ recipients during various years. Materials and Methods. Strains were examined for the presence of different genes determining vancomycin resistance: vanA, vanB, vanD, or vanG by polymerase chain reaction (PCR). Restriction fragment length polymorphism (RFLP)-pulsed field gel electrophoresis (PFGE) was performed on bacterial DNA digested with SmaI enzyme. Results. From 2003 to 2006, we isolated 12 strains of VREfl from 8 patients (2 liver and 6 kidney transplantations). All strains harbored the van4 gene. Among the strains, 5 displayed patterns similar to each other, despite being isolated from different patients, and were susceptible to ampicillin with high resistance to aminoglycosides. Conclusions. These results suggested that a single strain of VREfl was present for 3 years in closely related hospital wards, but it disappeared in the following years.